This isn't a public beta yet. I thought I'd give the die hard pngout users here a first crack at the beta.
Please send any issues or feedback to customer-service@ardfry.com
System Requirements Mac OS X 10.4 Photoshop CS2 update 9.0.2, or Photoshop CS3. It may also work with Elements for Mac. The download for this has disappeared, so I couldn't test it.
Installation Instructions: Copy the plugin to Photoshop/plug-ins/file formats. You should then have the PNGOUT file type in the Open, Save, Open as, and Save as dialogs.
This is a universal binary. If you are running an older version of Mac OS X or Photoshop, then I can post a PPC only build, but I don't know if it will work. I am interested in knowing if supporting these older versions is possible, but I don't have a test environment for these.